Here are some of the primary purposes of geotextiles in construction:

Filtration

Geotextiles are commonly used as filtration barriers to prevent the migration of fine particles from one soil layer to another while allowing the passage of water. They are placed between soil layers or beneath drainage systems to retain soil particles and prevent clogging.

Drainage

Geotextiles with high permeability are utilized as drainage materials to facilitate the flow of water within soil or drainage systems. They can be used in applications such as retaining walls, roadways, athletic fields, and landfills to prevent water buildup and promote effective drainage.

Separation

Geotextiles are used to separate different soil layers or materials with contrasting properties, such as soil and gravel or soil and geomembranes. By preventing mixing or intermixing between layers, geotextiles maintain the integrity and performance of engineered structures, such as roadways, railroad beds, and embankments.

Erosion Control

Geotextiles are employed in erosion control applications to stabilize soil surfaces and prevent soil loss due to water runoff or wind erosion. They can be installed as erosion control blankets, mats, or geotextile tubes to protect slopes, embankments, shorelines, and vegetated areas from erosion.

Reinforcement

Geotextiles are used to reinforce soil structures and improve their stability, strength, and load-bearing capacity. They are commonly incorporated into retaining walls, reinforced earth structures, steep slopes, and soft soil foundations to provide additional tensile strength and confinement to the soil.

Protection

Geotextiles serve as protective barriers to shield geomembranes, liners, and other vulnerable components from damage caused by punctures, abrasion, and UV degradation. They are installed as cushioning layers or protective covers to extend the service life and performance of underlying materials.

Subsurface Drainage

Geotextiles are utilized in subsurface drainage systems to wrap and protect perforated pipe, aggregate drains, or drainage cores. They act as filter fabrics to prevent soil particles from entering drainage channels and clogging the system, ensuring efficient water removal from the soil.

Overall, the purpose of geotextiles in construction is to provide engineered solutions for soil stabilization, drainage, filtration, separation, erosion control, reinforcement, and protection. By addressing specific geotechnical challenges and site conditions, geotextiles contribute to the sustainability, longevity, and performance of civil engineering and infrastructure projects.